Grinding and polishing machine



Jan, 26 1926.

F. KUHN Er AL GRINDING AND PQLISHINGA MACHINE gnomo Yum- Kum LAURMCELTMMAS Jan. 26,1926. 1,570,684V

F. KUHN ET AL GRINDING AND POLISHING MACHINE l Filed July 24, 1922' 2 sheets-Sheet 2 vwemtom RAMI. DNN

Patented Jan. 26, 1926.

UNITED STATES PATENT OFFICE.

FRANK KUHN AND LAURENCE H. THOMAS, 0F DETROIT, MICHIGAN, ASSIGNORS TO AMERICAN ELECTRICAL HEATER COMPANY, OF-DETROIT, MICHIGAN, A CORPORA- TION MICHIGAN.

applicati@ med Juiy `24, 1922. vserial No. 577,188.

To all Q01/0m t may concern.'

Be it known that we, FRANK KUHN and LAURENCE H. THOMAS, both citizens of the United Statesof America, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new `and useful Improvements in Grinding and Polishing Machines, of which the following is a specification, reference being had therein to the accompanying drawings. y

The invention relates to grinding and polishing machines and is especially vadapted for the grindingand polishing of flat-work pieces,y such as the base of an electric 'flatiron.

One of the yobjects ofthe invention is to obtain a machine which is adaptedfor large production, 'whereby `the work may be completely finished injone operation.

Another object is to provide a machine vwhich will produce a high polish on the work. Stillt other objects reside in the novel features of `construction and the lcombination of parts as hereinafter set forth, a'nd shown in the accompanying drawings, whereiny Figurell is a side elevation of the complete machine;

Figure-2 is an end elevation thereof;

Figure 3 is a vertical section on the line 3:-3 ofi-Figure 1;

Figure 4 is` a plan view of the work conveyor; f l

Figure 5 is al vertical section on the line 5 5 of Figure 4"; n

Figure 6 is a vertical section on the line 6-6 of Figure 2.

In general construction the machine consists of a plurality of grinding u-nitsfwhich are arranged in operative relation with a travelingwork holder, which presents they work successively to the different units. Preferably the grinding units arey provided with-different grades ofabrasive, whereby the first unit performs the rough grinding and the last unit gives thework its finishing polish.

i While the grinding units may be ofy any suitable construction, in the preferred form, they consist ofa pair of rotatable wheels and a travelingV abrasive belt operating thereover. The work-piece is moved tangentiallyof-one ofthe wheels and is yieldingly pressed radiallyfthereof in order to bring the'work piece in contact with that portion of thel abrasivebelt which is supported by said wheel.

In carrying out this-construction we preferably provide a plurality of vertical hollow posts 1 which are suit-ably supported on bases 2. Adjustable collars 3 and 3are slidably mounted on the posts 1 andare secured thereto by suitable Ymeans such as the screws 4. The collars 3 and 3 are provided with outwardly*extending arms 5, in which are rotatably mounted the arbors 6 and 6. Wheels or pulleys 7 and 7 are mounted upon the respective arbors and an endless abrasive beltS operates thereover.

p For vertical adjustment of the grinding unit ythe rod 9 extends within they hollow post 1 and is provided with collars 10 and 10 on either side of a disk 11 which is secured to the post 1. The lower end of the rod 9 is threaded and engages with a disk 12, whichis secured by means of screws 14 to 'ag tubular member 13 telescopically `engaging the post 1. The member 13 is supported by a bracket 15 which is securedto the frame member 16 hereinafter more fully described. The tubular post 1 is provided with lvertical slots 17 'through which the screws 14 extend, so that byturning the lrod 9 a relative movement is obtained between p the disks 11 and '12, thereby moving the tubular post 1 within the member 13 and raising or :lowering the grinding unit with respect to the frame member 16. The upper end of the rod 9 is preferably provided with a squared portion 9EL for engagement with a handle wrench 18.

For operating the. belts S, separate motors 19 are preferably provided for each unit.l the motors being suitably supported on the posts 1 by means of brackets 20. The motors are connected to the pulleys 7 by suit-` able means suclras the chain belts 21.

yFor bringing the Vwork into operative relation with the various grinding units, an endless conveyor 22 is provided which con'- sists of the sprocket wheels 23 and 23 over which operates the chain 39. The-sprocket wheel v23 is mounted upon Van arbor 24, which is journaled in aframe 25 consisting of the vertical legs 26 and any suitable cross members 27, bracing and stiflening the frame. A separate motor 28 is supported on a platform 29 in the frame 25 and is connected to the sprocket wheel 23 by suitable gearing. As shown, the motor shaft 30 is connected to a countershaft 31 by means of the pulleys 32 and 33 and the belt 34. A worm 35 on the countershaft meshes with a worm wheel 36, which in turn drives a gear 37 upon the shaft 24 by means of a pinion 38. The sprocket wheel 23 is journaled in the opposite end of the frame 25 and is provided with a suitable take-up for regulating the tension of the chain 39. As shown, the takeup consists of blocks 40 which are longitudinally slidable in the guideways 41 and are adjustable by means of screws 42 which threadedly engage the frame legs 262'- and are secured to the blocks 40.

The frame vmember 16, previously re terred to, extends longitudinally of the frame 25 and is secured to the vertical legs 26. A similar frame member 16n secured in the same manner forms with the member 16 a support for the conveyor. The endless chain 39 consists of links 43 having cross members 44 which engage with the teeth of the sprocket wheels 23 and 23. Each of the links 43 supports a rectangular plate 45 which is provided with upstanding pms 46 for positioning and holding the workpiece 47 thereon. As shown in the drawings, the workpiece is the base of an electric 'flatiron and the pins 46 are arranged upon the plate 45 to correspond with apertures 48 in the base, which are used in assembling' the same.

For guiding the plates 45 the side members 49 and 49 are secured to the longitudinal fram-e members 16 and 16a respectively and angle irons 50 and 50 are fastened thereto, so that the horizontal portions 51 and 51 form stops tor limiting the upward movement of the plates 45. 'Under each of the wheels 7 is located suitable means for yieldingly pressing the work into operative relation with the abrasive belt and, as shown, this means includes levers 52 which are pivoted upon shafts 53 extending transversely of the frame. Each of the levers 1s provided with a weight 54 which is hung in the notches 55 in one end of the lever. The other end of the lever bears against a cross rod 56 having vertically extending portions 57 and 57 which are slidable in vertical holes 58 in the longitudinally extending members 59. The rods 57 and 57 are provided at their ends with transversely eX- tending members 60 and 60 which bear against the under side of the plates 45. Thus the weight, acting through the lever arm, vieldingly presses the plates 45 towards the wheel 7 and the angle bars 50 and 5G form stops which prevent the plates from contacting with the wheel. The pressure may be varied by adjusting the position of the weight 54 and thereby increasing or dccreasing the effective leverage.

E or convenience in changing the belts, it is desirable to move the grinding units away from the conveyor and for this purpose each of the posts 1 is provided with a pedal 61 which serves this function. rthe pedal 61 is located at one end of a lever 62, which is tulcrumed upon lugs 63 on the base 2. rllhe opposite end of the lever 62 is bifurcated and the arms 64 are connected by a transversely extending rod 65, which is secured to the tubular post l. The base 2 is slotted to permit the movement of the rod 65. 1With this arrangement, when pressure is applied to the pedal 61, the tubular post 1 is raised relative to the base 2 and in this movement carries the grinding unit vertically a sutlicient distance to withdraw it from operative position with respect to the work conveyor.

In the operation of the machine, the grinding units are provided with different grades of abrasive belts ranging from the coarsest grade for rough grinding the work to the iinest grade for giving it the finishing polish. Each of the units is setin operation by starting the respective motors 19 and the conveyor is set in motion by the motor 28. The grinding units are adjusted relative to the conveyor and the pressure on the respective units is adjusted by means of the weights 54. The workpieces 47 are then placed upon the conveyor and positioned by means of the pins 46. The workpieces are thus carried into operative relation with each of the grinding units, and after completing the operation, may be removed from the conveyor at the opposite endthereof.

TWhat we claim as our invention is:

1. A grinding and polishing machine comprising a horizontal trame, a pair oi sprockets j ournalled in opposite ends thereof, an endless link chain engaging said sprockets, plates. secured to the links of said chain, longitudinal guide ways on said frame for receiving the edges of said plates, flanges extending inwardly from said guide ways forming stops for said plates to limit the upward movement thereof, levers pivoted to said frame, weights depending from the ends of said levers, a vertically movable rod attached to cach of said levers at the end opposite said weights, and a head on said red adapted to bear against the under side or" said plate, said head being arranged beneath one ot said flanges.

2. In a grinding and polishing machine, the combination with a traine having spaced longitudinal side members, a pair sprocket wheels, an endless chain engaging said sprockets and adapted to move intermediate. sait side members, said chain having a series of links, a plate attached to one of said links, a pair of vertically movable rods guided in said side members and extending beneath the side edges of said plate, a cross member connecting said rods, a-lever pivoted to said frame having one end engaging` said cross member, a weight on the opposite end of said lever',- a rotatable grinding unit adapted to engage the work carried by saidv plate and flanges extending inwardly from said'side members forming a stop for 10 tures.

FRANK KUHN. LAURENCE H, THOMAS. 

